Science, Technology, Engineering, and Mathematics Books

Living Fossils

When I was a kid, my favorite book was my dad’s geology text. I spent hours and hours leafing through the pages, studying drawings of fossils and dinosaurs, losing myself in the geological time scale, sounding out “Carboniferous” and “Silurian”.

Mostly, when we think of fossils, it’s dinosaurs and trilobites. Something preserved in rock. Extinct.

But what if some of those ancient creatures still lived among us? Would we recognize them?

In this book, Caroline Arnold shows us six amazing creatures that resemble their long-gone, ancient relatives. She shows us where they live, how they survived extinction, and what their future holds. One of these “living fossils” is the horseshoe crab. One hundred fifty million years ago, horseshoe crabs had hard shells and long tails. They crawled up on sandy beaches to search for worms and shellfish to eat.

Not much has changed in the intervening millennia… if you visit the east coast on a warm summer night when the moon is full, you’ll probably see hundreds of horseshoe crabs pull themselves onto the beach. They’re digging nests and laying eggs, just as they did millions of years ago.

You don’t need to drive to the beach to find a living fossil; just head outside to a wetland or meadow and look for dragonflies. These keen mosquito-devouring aerial hunters are the great-great-great-/…/ great-grandchildren of dragonflies that lived 280 million years ago. Over time things changed, like size. Back then, dragonflies were a lot bigger – about the size of a crow!